1. Field of the Invention
The present invention generally relates to electrical connectors and, more particularly, to a printed circuit panel connector comprising a heat sink therein such that all electrical connections to the printed circuit panel connector are maintained at substantially the same temperature.
2. Description of the Prior Art
An undesirable feature in conventional printed circuit panel connectors, which are utilized as an interface between a plurality of external conductors and the terminals of say a printed circuit board, is the inability to maintain all electrical connections at the printed circuit panel connector at essentially the same temperature (printed circuit is hereinafter referred to as PC). This undesirable feature is a serious handicap in electrothermic applications such as, for example, PC assemblies for thermal measuring communication power systems, of which the following are a few of the several types possible: data acquisition systems, data logger systems, and scanner systems. As is well known, the circuitry consisting of the electrical connections that interface with the PC connectors used in the above systems, as well as the printed circuitry of the PC boards and/or assemblies, may incorporate therein a variety of electrothermic devices or instruments like: thermocouples, thermistors, bridge transducers and bolometers, etc.
The operation of these devices, generally speaking, depends upon the heating effect of current flow seen by the electrical connections circuitry. They are employed to detect, measure, or indicate thermal characteristics or data. However, when employed in the network of electrical connections in conventional PC connectors, the acquired thermal data is for the most part useless, or inaccurate and unreliable at best, if the several electrical connections are not maintained at an even, constant, and substantially identical temperature throughout the interval of time required to obtain the desired thermal data. Unequal temperatures along the electrical connections virtually destroy all chances for obtaining accuracy, reliability, and repeatability. Repeatability being herein used to mean the ability to acquire successive and accurate readings during the time interval designated to collect the desired thermal data.
Several approaches in PC connector design have been made with the objective to produce a PC connector capable of eliminating this elusive undesirable feature. One such common practice of which applicants are aware is to insert a removable rectangular sheet configured heat sink between rows of contact elements received within corresponding tubular connectors in a terminal block. Each contact element is adapted to be electrically connected between its complementary tubular connector and a corresponding PC board terminal, with physical contact between the tubular connector and the heat sink being made subsequent to the latter's insertion between the rows of contact elements.
However, this practice fails to effectively eliminate the aforesaid undesirable feature because irregularities in the sheet configured surface of the heat sink often prevents the heat sink from making positive contact with all of the tubular connectors. In addition, pressing forces required to insert and/or remove the heat sink frequently either break some of the contact elements within the socket of the connector, or open the connection between the heat sink and some of the tubular connector elements. Still further, the foregoing practice involves fabricating the connector from a multiple number of connector parts and a multiple number of contact element parts, and involves the use of fastener hardware, which consequently increases material, tooling, machining and overall manufacturing costs. Finally, the known multiple-piece constructed connectors increase the chance of wider than expected tolerances occuring between mating parts which, in turn, also may result in lack of positive contact between the heat sink and many of the contact elements of the connectors.
In another prior art approach known to applicants, a conventional PC panel connector has heat sinks mounted upon an external surface of the connector; however, this solution is disadvantageous since externally mounted heat sinks are often cubersome or unwieldy, and thus, waste precious space on the connector otherwise suitable for external connector positions and PC panel terminal positions.
Against the foregoing background, it is an object of this invention to provide an improved arrangement between a heat sink, a plurality of tubular electrical connector elements, and a corresponding plurality of electrical contact elements within the body of a PC panel connector.
It is another object of this invention to provide a PC connector heat sink that is capable of maintaining all electrical connections to a PC edge-board connector of substantially the same temperature.
It is a further object of this invention to provide a PC edge-board connector, in the form of a terminal block, whereby an encased heat sink is uniquely disposed among an encircling plurality of ordered electrical contact elements and a plurality of tubular electrical connector elements thereby to optimize available space for such connector element positions and PC board terminal positions.
It is an additional object of this invention to provide a PC edge-board connector having a plurality of onepiece electrical contact elements that are positively retained within the block, by an encapsulated heat sink, to prevent movement thereof when subjected to shock and vibratory environmental conditions.
It is yet another object of this invention to provide a unitary PC edge-board connector comprising an encased heat sink and which is relatively inexpensive to fabricate.
It is still another object of this invention to provide a PC edge-board connector, of a unitary terminal block configuration, applicable in PC assemblies for thermal measuring communication power systems, which includes an encased heat sink uniquely arranged among an ordered plurality of tubular electrical connector and electrical contact elements, for maintaining all interfacing electrical connections to the connector at substantially the same temperature, thereby enabling accuracy, reliability, and repeatability of determined thermal data.